Wallpaper is held to a surface, e.g. a wall, using a paste that can be based on a polycarbohydrate, e.g., starch or cellulose. The paste is applied to the wallpaper and forms a bond between the wallpaper and the surface.
To remove the wallpaper, the bond must be degraded without harming the underlying surface as by removing part of the surface or leaving wallpaper thereon. It is desirable to remove the wallpaper with as little force, such as existed using a scraper, as possible to avoid damaging the underlying surface.
Steam generating devices are known to assist in removal. The steam typically only rehydrates the paste. If the person removing the wallpaper permits the rehydrated paste to dry too much before attempting to remove the wallpaper, the paste can rebond the wallpaper to the wall making removal more difficult. Care must be taken so that the steam does not harm the underlying surfaces. Steam is also messy and expensive.
Liquid wallpaper strippers are known for removing wallpaper using an active ingredient that acts on the bond. Wallpaper having a liquid impermeable layer, such as vinyl wallpaper, must be scored or perforated to permit penetration of the liquid. The liquid helps maintain an environment in which the active ingredient is effective. Moisture can be lost due to evaporation of the liquid prior to the active ingredient penetrating the wallpaper and acting on the bond. Evaporation can change the environment to one in which the active ingredient is not effective. This rapid evaporation requires that the stripper be reapplied to the wallpaper to maintain the necessary moisture and environmental conditions. Some liquid strippers have a relatively low concentration of the active ingredient to maintain stability of the stripper. The low concentration requires the use of excessive amounts of the stripper in order to attain a concentration at the bond effective to act on the bond. The repeated application of the stripper to maintain the moisture and the environment or obtain the desired concentration is time consuming, expensive and can cause moisture-related damage to the underlying surface.
The active ingredient must come in contact with the bond to be effective. If the stripper does not facilitate penetration of the wallpaper by the active ingredient, then the time period required to remove the wallpaper may be excessive. The excessive time period can also permit more moisture loss requiring reapplication of the stripper which is costly.
A wallpaper stripper that overcomes at least one of the aforementioned shortcomings of existing wallpaper removal systems is highly desirable.